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 * and Distribution License("CDDL") (collectively, the "License").  You
 * may not use this file except in compliance with the License.  You can
 * obtain a copy of the License at
 * https://github.com/payara/Payara/blob/main/LICENSE.txt
 * See the License for the specific
 * language governing permissions and limitations under the License.
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 * file and include the License file at legal/OPEN-SOURCE-LICENSE.txt.
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 * GPL Classpath Exception:
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 * exception as provided by the Payara Foundation in the GPL Version 2 section of the License
 * file that accompanied this code.
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 * If applicable, add the following below the License Header, with the fields
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package fish.payara.microprofile.metrics.rest;

import static fish.payara.microprofile.Constants.CREATE_INSECURE_ENDPOINT_TEST;
import fish.payara.microprofile.metrics.admin.MetricsServiceConfiguration;
import static java.util.Arrays.asList;
import java.util.Map;
import java.util.Set;
import jakarta.servlet.HttpConstraintElement;
import jakarta.servlet.ServletContainerInitializer;
import jakarta.servlet.ServletContext;
import jakarta.servlet.ServletException;
import jakarta.servlet.ServletRegistration;
import jakarta.servlet.ServletSecurityElement;
import static jakarta.servlet.annotation.ServletSecurity.TransportGuarantee.CONFIDENTIAL;
import static org.glassfish.common.util.StringHelper.isEmpty;
import org.glassfish.internal.api.Globals;

public class MetricsServletContainerInitializer implements ServletContainerInitializer {

    @Override
    public void onStartup(Set<Class<?>> set, ServletContext ctx) throws ServletException {

        MetricsServiceConfiguration configuration = Globals.getDefaultBaseServiceLocator()
                .getService(MetricsServiceConfiguration.class);
        if (!"".equals(ctx.getContextPath())) {
            return;
        }

        // Check if there is already a servlet for metrics
        Map<String, ? extends ServletRegistration> registrations = ctx.getServletRegistrations();
        for (ServletRegistration reg : registrations.values()) {
            if (reg.getClass().equals(MetricsResource.class)) {
                return;
            }
        }

        String virtualServers = configuration.getVirtualServers();
        if (!isEmpty(virtualServers)
                && !asList(virtualServers.split(",")).contains(ctx.getVirtualServerName())) {
            return;
        }

        // Register a servlet with url patterns of metrics handlers
        ServletRegistration.Dynamic reg = ctx.addServlet("microprofile-metrics-resource", MetricsResource.class);
        reg.addMapping("/" + configuration.getEndpoint() + "/*");
        if (Boolean.parseBoolean(configuration.getSecurityEnabled())) {
            String[] roles = configuration.getRoles().split(",");
            reg.setServletSecurity(new ServletSecurityElement(new HttpConstraintElement(CONFIDENTIAL, roles)));
            ctx.declareRoles(roles);
            if (Boolean.getBoolean(CREATE_INSECURE_ENDPOINT_TEST)) {
                ServletRegistration.Dynamic insecureReg = ctx.addServlet("microprofile-metrics-resource-insecure", MetricsResource.class);
                insecureReg.addMapping("/" + configuration.getEndpoint() + "-insecure/*");
            }
        }
    }
}
